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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_005_524">&nbsp;</a>NAME</h4><blockquote>
getenv - get value of an environment variable
</blockquote><h4><a name = "tag_000_005_525">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="stdlib.h.html">stdlib.h</a>&gt;

char *getenv(const char *<i>name</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_000_005_526">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>getenv()</i>
function searches the environment list for a string of the form
"<i>name=value</i>",
and returns a pointer to a string containing the
<i>value</i>
for the specified name.
If the specified name cannot be found, a null pointer is returned.
The string pointed to must not be modified by the application, but
may be overwritten by a subsequent call to
<i>getenv()</i>
or
<i><a href="putenv.html">putenv()</a></i>
but will not be overwritten by a call to any other function in this document.
<p>
This interface need not be reentrant.
</blockquote><h4><a name = "tag_000_005_527">&nbsp;</a>RETURN VALUE</h4><blockquote>
Upon successful completion,
<i>getenv()</i>
returns a pointer to a string containing the
<i>value</i>
for the specified
<i>name</i>.
If the specified name cannot be found a null pointer is returned.
<p>
The return value from
<i>getenv()</i>
may point to static data which may be overwritten by subsequent calls to
<i>getenv()</i>
or
<i><a href="putenv.html">putenv()</a></i>.
</blockquote><h4><a name = "tag_000_005_528">&nbsp;</a>ERRORS</h4><blockquote>
No errors are defined.
</blockquote><h4><a name = "tag_000_005_529">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_005_530">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_005_531">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_005_532">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="exec.html">exec</a></i>,
<i><a href="putenv.html">putenv()</a></i>,
<i><a href="stdlib.h.html">&lt;stdlib.h&gt;</a></i>,
the <b>XBD</b> specification, <a href="../xbd/envvar.html"><b>Environment Variables</b>&nbsp;</a>.
</blockquote><h4>DERIVATION</h4><blockquote>
Derived from Issue 1 of the SVID.
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
<br> [ <a href="../index.html">Main Index</a> | <a href="../xshix.html">XSH</a> | <a href="../xcuix.html">XCU</a> | <a href="../xbdix.html">XBD</a> | <a href="../cursesix.html">XCURSES</a> | <a href="../xnsix.html">XNS</a> ]

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